Audi Repair: 2002 Audi TT 2.0T Fuel Gauge and Huming, exhaust leaks, fuel gauge

Question
Good Evening, In my TT when the fuel gauge reads a little over 1/4 Full gas light comes on (at 1/4 gas is almost gone). When I fill up tank the gauge goes WAY beyond full on gauge. Is this the sensor in the gas tank or something else. Second the car seemly is getting a little louder in idle. Not a high RPM just a louder idle noise. Is this sludge in the engine, and if so how can I get rid of it. THANK YOU  

Answer
hello
You will need to check the gauge first, with VAG do output test of gauges. If the gauge goes to zero and to full with all the others - gauge is OK and the problem is with the sender inside the tank.
Sorry , but we do not have 2.0T engines in USA> so do not know much about them. Sludge will not cause engine to run louder, make sure there is no any exhaust leaks.
good luck                       Greg